The present invention relates to a Petri dish for cultivating micro-organisms, which consists of two members, i.e. a receptacle and an additional lid and which both have a revolution shape.
Such Petri dishes are widely used notably in laboratories and these dishes are provided in order to be superposed so as to form stacks. This notably allows the operators to form different batches of Petri dishes, for example so as to sort them out according to the nature of the culture which is made therein. Documents JP-2003 047459, JP-2003 102463, US-2002/045245 and U.S. Pat. No. 4,160,700 illustrate the state of the art in this matter. However, if this dish stacking function is possible, to this day, there does not exist any means which allows retention of the dishes attached to each other.
Also, up to now, the handling of culture dishes requires the use of transport containers and of external systems for attaching the dishes together. Thus, it is common that the users make use of an elastic or of adhesive tape for securing the dishes together. It is understood that the use of external means involves control of their sanitary quality, and therefore of their sterilization. In certain cases, these constraints for handling and transporting Petri dishes are solved by using an additional disposable transport tool, thereby allowing the displacement of a batch of dishes from one place to another, which in all the scenarios involves an additional cost.
The present invention has the object of solving these difficulties. For this purpose, it proposes a Petri dish which consists of two members, i.e. a receptacle and an additional lid, which both have an axisymmetrical shape (revolution shape) and which are each delimited by a bottom wall and at least one peripheral wall, that said receptacle and lid bearing additional locking means laid out so that, upon forming a stack formed with the superposition of at least two dishes, the locking means borne by a first member of a first dish may cooperate with locking means of the second member of the second dish, making them thus interdependent on each other, one of said members including a peripheral wall which extends above and below the bottom wall, while the other one is dimensioned so that, upon forming said stack, said member of a first dish is partly engaged into the other member of a second dish, in a housing delimited by the bottom wall and a portion of said wall, characterized by the fact that said additional locking means are able to cooperate by a relative rotary movement of one dish relatively to the other, that said locking means are borne by the peripheral walls and that they consist in protrusions. Thus, according to the invention, the members which make up each of the Petri dishes integrate within themselves means for locking to another dish. By their presence, it is therefore possible to form stacks of dishes, in which each dish is made interdependent on its neighbor(s) so as to form an assembly which may be handled without any other external connection means.
According to advantageous and non-limiting characteristics of this dish:                said protrusions are at least two in number, are angularly equidistant and extend over an angular fraction of said wall;        said protrusions have the shape of portions of mating (complementary) helicoidal ribs;        the bottom wall of one of said members bulges outwards and is elastically deformable so that it occupies a substantially planar position. Other characteristics and advantages of the present invention will become apparent upon reading the detailed description which follows, of a preferential embodiment.        